This turned out more tricky then expected. Originally the
KAboutData was assigned to a non-existing QApplication object.
Somehow this was prevending the later crashes, if the QApplication
was initialized before KAboutData and we were creating QWidgets.

The problem turned out to be the referenced arguments to
QApplication. While we already passed the command arguments from
allocated / heap memory, the argc argument was just the local
stack variable!
The simple fix is to allocate an int to pass to QApplication and
the crashes are gone when assigning KAboutData after QApplication.
Also removes some Qt initialization warnings on startup.

Change-Id: Ic5b1eea578039fd5875097d23de587b970a6dfca